diff -r 7b892c48e289 -r d345b109672f src/Tools/isac/ProgLang/Prog_Expr.thy
--- a/src/Tools/isac/ProgLang/Prog_Expr.thy	Wed Sep 18 17:23:02 2019 +0200
+++ b/src/Tools/isac/ProgLang/Prog_Expr.thy	Sun Sep 22 14:47:35 2019 +0200
@@ -5,7 +5,7 @@
 *)
 
 theory Prog_Expr
-  imports Calculate
+  imports Calculate ListC
 begin
 
 text \<open>Abstract: